Childhood is analogous to language learning. It has a biological basis but cannot be realized unless a social environment triggers and nurtures it, that is, has need of it. If a culture is dominated by a medium that requires the segregation of the young in order that they learn unnatural, specialized, and complex skills and attitudes, then childhood, in one form or another, will emerge, articulate and indispensable.
Ch. 9 : Six Questions - The Disappearance of Childhood (1982)